反应详情

5-Bromothiazol-2-yl isocyanate dimer (17.0 grams), benzene (70 ml) and the dimethyl acetal of 2-methylaminoacetaldehyde (13.5 grams) were charged into a glass reaction vessel equipped with a mechanical stirrer and thermometer. The reaction mixture was then stirred at room temperature for a period of about 1 hour. After this time the reaction mixture was filtered, and the filtrate was stripped of solvent under reduced pressure, leaving an oil. This oil was chromatographed on silica gel using ethyl acetate as the diluant. The eluant was dissolved in an ethanol-water mixture and the solution was filtered. The filtrate was then stripped of solvents under vacuum to yield the desired product the dimethyl acetal of 2-[1-methyl-3-(5-bromothiazol-2-yl)ureido]acetaldehyde as a crystalline solid having a melt point of 72° to 73° C.

1. customequipped with a mechanical stirrer
2. filtrationAfter this time the reaction mixture was filtered
3. customleaving an oil
4. customThis oil was chromatographed on silica gel
5. dissolutionThe eluant was dissolved in an ethanol-water mixture
6. filtrationthe solution was filtered